From 0a196848ca365ec582c6d86659be456be6d4ed96 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 30 Oct 2013 21:16:22 +0100 Subject: perf: Fix arch_perf_out_copy_user default The arch_perf_output_copy_user() default of __copy_from_user_inatomic() returns bytes not copied, while all other argument functions given DEFINE_OUTPUT_COPY() return bytes copied. Since copy_from_user_nmi() is the odd duck out by returning bytes copied where all other *copy_{to,from}* functions return bytes not copied, change it over and ammend DEFINE_OUTPUT_COPY() to expect bytes not copied. Oddly enough DEFINE_OUTPUT_COPY() already returned bytes not copied while expecting its worker functions to return bytes copied. Signed-off-by: Peter Zijlstra Acked-by: will.deacon@arm.com Cc: Frederic Weisbecker Link: http://lkml.kernel.org/r/20131030201622.GR16117@laptop.programming.kicks-ass.net Signed-off-by: Ingo Molnar --- kernel/events/internal.h | 35 ++++++++++++++++++++++++++--------- 1 file changed, 26 insertions(+), 9 deletions(-) (limited to 'kernel/events/internal.h') diff --git a/kernel/events/internal.h b/kernel/events/internal.h index ca6599723be5..569b218782ad 100644 --- a/kernel/events/internal.h +++ b/kernel/events/internal.h @@ -82,16 +82,16 @@ static inline unsigned long perf_data_size(struct ring_buffer *rb) } #define DEFINE_OUTPUT_COPY(func_name, memcpy_func) \ -static inline unsigned int \ +static inline unsigned long \ func_name(struct perf_output_handle *handle, \ - const void *buf, unsigned int len) \ + const void *buf, unsigned long len) \ { \ unsigned long size, written; \ \ do { \ - size = min_t(unsigned long, handle->size, len); \ - \ + size = min(handle->size, len); \ written = memcpy_func(handle->addr, buf, size); \ + written = size - written; \ \ len -= written; \ handle->addr += written; \ @@ -110,20 +110,37 @@ func_name(struct perf_output_handle *handle, \ return len; \ } -static inline int memcpy_common(void *dst, const void *src, size_t n) +static inline unsigned long +memcpy_common(void *dst, const void *src, unsigned long n) { memcpy(dst, src, n); - return n; + return 0; } DEFINE_OUTPUT_COPY(__output_copy, memcpy_common) -#define MEMCPY_SKIP(dst, src, n) (n) +static inline unsigned long +memcpy_skip(void *dst, const void *src, unsigned long n) +{ + return 0; +} -DEFINE_OUTPUT_COPY(__output_skip, MEMCPY_SKIP) +DEFINE_OUTPUT_COPY(__output_skip, memcpy_skip) #ifndef arch_perf_out_copy_user -#define arch_perf_out_copy_user __copy_from_user_inatomic +#define arch_perf_out_copy_user arch_perf_out_copy_user + +static inline unsigned long +arch_perf_out_copy_user(void *dst, const void *src, unsigned long n) +{ + unsigned long ret; + + pagefault_disable(); + ret = __copy_from_user_inatomic(dst, src, n); + pagefault_enable(); + + return ret; +} #endif DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user) -- cgit v1.2.3